body,
div,
span,
a {
    margin: 0;
    padding: 0;
}

#my2048 {
    margin-left: auto;
    margin-right: auto;
    position: relative;
    top: 200px;
    /* background: #bbada0; */
    background: rgba(50, 50, 50, .5);
}

#my2048 div {
    position: absolute;
    display: inline-block;
    border: 0px;
}

.f-return a img {
    position: absolute;
    left: 0;
    top: 0;
    margin: 10px;
    width: 50px;
    height: 50px;
    cursor: pointer;
}